These rock crystals are made from a mineral called gypsum and they are over a meter long.

这些岩晶种叫做膏的矿物构成，长度过米。

And then those are an ancestor of Liezenstein and reading stones, which I think were often made of something like rock crystal.

然后这些是利森斯坦的祖先，我认为它们通常是类似岩水晶的材料制成的。